JP2000296192A - Iron type golf club head - Google Patents

Abstract

(57) [Problem] To provide an iron type golf club head which is easy to hit and inexpensive. SOLUTION: This is an iron-type golf club head 1 having a head body 2 provided with a shaft mounting portion 2b on a heel h side of a face base 2a on which a face surface F is formed, and a weight member 3. The face base 2a is made of a low-specific-gravity material having a specific gravity of 5.0 or less, and has a plate-like portion 4 forming the face surface F, protruding at the peripheral edge toward the back face side, and extending in an annular shape along the peripheral edge and at the sole side. And a rib 5 having a notch 6 formed by cutting out the rib. The weight member 3 is made of a high specific gravity material having a specific gravity of 7.0 or more, and has an annular base 7 formed along the inner wall surface 5i of the rib 5 and the notch formed on the sole side of the annular base 7. And a sole weight piece 9 which is fitted into the part 6 and forms a part of the surface of the sole s.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an iron type golf club head which can be easily hit and can be manufactured at low cost.

[0002]

2. Description of the Related Art Conventionally, iron-type golf club heads (hereinafter sometimes simply referred to as "heads") include soft iron, stainless steel, and the like.
In addition to metal materials such as zinc alloys, materials such as fiber reinforced resins have been commonly used.In recent years, however, low sweeteners have been used to increase the sweet area and minimize the loss of flight distance when missed. A combination of a specific gravity material and a high specific gravity material has been proposed. For example, Japanese Patent No. 2850
In Japanese Patent Publication No. 314, as shown in FIG. 10 and FIG. 11, which is a cross section taken along line DD, a head body a provided with a shaft mounting portion a2 for mounting a shaft on a heel side of a face base a1 on which a face surface F is formed. A head composed of a material having a high specific gravity and an annular weight c disposed along the outer periphery of the back surface b is disclosed on the back surface (back face) b of the head body a.

[0003] In such a head, the weight can be distributed more to the periphery of the head and to the sole s side, and the sweet area can be expanded by increasing the moment of inertia and lowering the center of gravity, and the ball can be easily raised. Is possible. However, since the weight c is provided along the outer periphery of the back surface b of the head body a1, the head body a
A boundary line e between 1 and the weight c is formed continuously over the outer peripheral surface of the head, that is, over the sole s, the toe t, and the top portion g. Therefore, in such a head, a high-precision finishing step is required so that the surfaces of different members (the head main body a1 and the weight c) appearing on the outer peripheral surface of the head having a complicated shape are flush with each other without any step. ,
In comparison with the finishing process of the outer peripheral surface of the head made of one kind of material, it requires much more labor and time, and is inferior in productivity.
There are problems such as increasing the price of the head.

The present invention has been devised in view of the above-described problems, and it has been proposed that the boundary between the head body and the weight as described above appears on the outer peripheral surface of the head while improving the ease of hitting. It is an object of the present invention to provide an iron type golf club head which can be manufactured at a low cost by minimizing the finishing process of the outer peripheral surface of the head as much as possible.

[0005]

According to a first aspect of the present invention, there is provided a head body having a shaft mounting portion for mounting a shaft on a heel side of a face base on which a face surface is formed; Wherein the face base is made of a low specific gravity material having a specific gravity of 5.0 or less, and a plate-shaped portion forming the face surface, and a peripheral edge protruding to the back face side; A rib having at least one notch portion extending in an annular shape along the periphery and notching the sole side, wherein the weight member is made of a high specific gravity material having a specific gravity of 7.0 or more. An annular base formed along the inner wall surface; and a sole weight piece formed on the sole side of the annular base and inserted into the cutout to form a part of the sole surface. It is characterized in that.

Here, the low specific gravity material includes, for example, pure titanium or a titanium alloy, and the high specific gravity material includes, for example, stainless steel, a nickel-copper alloy, a tungsten alloy, or tungsten.

The notch includes a toe-side notch provided closer to the toe side and a heel-side notch provided closer to the heel side.
It may include a toe-side sole weight piece fitted into the toe-side notch, and a heel-side sole weight piece fitted into the heel-side notch.

It is preferable that a neck length L, which is a length from an upper end of the shaft mounting portion to a point where a center line of the shaft mounting portion intersects the horizontal plane, is 70 mm or less. When the shaft mounting portion is shortened in this way, it is desirable that the outer diameter D at the upper end of the shaft mounting portion be 13.2 mm or more.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view of the iron-type golf club head 1 of the present embodiment viewed from the back face side, FIG. 2 is an exploded view thereof, FIG. 3 (A) is a sectional view taken along line AA of FIG. (B) shows the same BB cross-sectional view. In the figure, a head 1 according to the present embodiment includes a head body 2 and a weight member 3.

The head body 2 is provided with a shaft mounting portion 2b for mounting a shaft (not shown) on a heel h side of a face base 2a on which a face surface F on which a ball is hit is formed. . In the present embodiment, the head body 2, that is, the face base 2a and the shaft mounting portion 2b, each having a specific gravity of 5.0 or less and being integrally formed of the same low specific gravity material, is exemplified.

As such low specific gravity materials, for example, pure titanium (specific gravity of about 4.5), titanium alloy (specific gravity of about 4.4 to
4.7), magnesium alloy (specific gravity of about 1.8 to 2.
3), duralumin (specific gravity of about 2.8) or aluminum-lithium (Al-Li) alloy (specific gravity of about 2.6). If the specific gravity is excessively small, the head is significantly increased in size in order to secure the minimum weight required for the head, and the contact area with the turf increases, so that the head tends to swing out poorly. From such a viewpoint, the low specific gravity material has a specific gravity of 1.5 or more, more preferably 3.
A value of 0 to 5.0 is desirable, and a titanium alloy having a high specific strength is particularly preferable in consideration of strength.

The face base 2a can be made lightweight by forming the face base 2a from a material having a low specific gravity.
As a result, more weight can be distributed around the head. The head main body 2 can be configured by combining two or more kinds of low specific gravity materials.

As shown in FIGS. 2 and 3, the face base portion 2a has a plate-shaped portion 4 forming the face surface F, a peripheral portion protruding toward the back face side and extending annularly along the peripheral edge. One or more notches 6 with notched sides
In this example, the rib 5 is formed with a concave portion C (a so-called cavity). The plate-shaped portion 4 has, for example, a thickness T1 of 3 to
It has a thickness of about 5 mm, and in this example, a substantially uniform thickness of about 4 mm, and a score line or the like is appropriately recessed on the face surface F.

In the present embodiment, the rib 5 extends continuously from the top portion g, the toe t, and the heel h of the head 1 in an annular shape, and is formed at a portion of the sole s other than the notch portion 6. . In this example, the amount by which the ribs 5 protrude from the plate-like portion 4 gradually increases from the top portion g toward the sole s. Further, two notches 6 of this example are formed including a notch 6A on the toe side provided near the toe t side and a notch 6B on the heel side provided near the heel h side.

A small-length rib 5 is interposed between the notch 6A on the toe side and the notch 6B on the heel side. Such a cutout portion 6 may be cutout by at least partially reducing the protruding amount of the rib 5, for example, in addition to the embodiment of FIG. 2 in which the rib 5 is completely removed from the plate-like body 4. . Further, in this example, an example in which the notch 6 is provided with a shaft body 11 projecting from the plate-shaped portion 4 to the back face side, for example, in a conical shape is illustrated.

The weight member 3 is formed of a high specific gravity material having a specific gravity of 7.0 or more. Here, as the high specific gravity material, for example, stainless steel (specific gravity of about 7.8 to 8.0), nickel-copper alloy (specific gravity of about 8.9), tungsten alloy (specific gravity of about 12 to 15), or tungsten (specific gravity of about 1 to 15)
8), platinum (specific gravity of about 21.3), copper alloy (specific gravity of about 8 to 1)
3) and the like. In consideration of workability, economy, and the like, stainless steel, nickel-copper alloy, tungsten alloy, or tungsten is particularly preferable. From a practical viewpoint, the specific gravity is preferably about 7.0 to 20.0.

In the present embodiment, the weight member 3 is formed in an annular shape along the inner wall surface 5i of the rib 5, and is inserted into the notch 6 formed on the sole s side of the annular shape. A sole weight piece 9 forming a part of the surface of the sole s, a backing material 10 having a thickness smaller than that of the annular base 7 and extending from the inner peripheral surface thereof along the plate portion 4 of the face base 2a. Are illustrated, and in this example, they are arranged so as to be exposed on the back face side.

The annular base 7 made of a material having a high specific gravity as described above is annularly disposed around the center of gravity G of the head 1 (shown in FIG. 4B). For this reason, the weight of the head 1 is distributed more to the peripheral portion of the head 1, and the moment of inertia can be increased. The weight member 3 is
Since the sole 5 includes a sole weight piece 9 which is inserted into the notch 6 in which the rib 5 is cut off on the sole s side to form a part of the surface of the sole s, the weight of the head 1 is also larger on the sole side. Allocated to promote low center of gravity. As a result, in the head 1, the height Sh of the sweet spot SS (shown in FIG. 4B), which is a perpendicular foot drawn from the center of gravity G to the face surface F, becomes low, and the hit ball has a high launch angle and low back. The hit amount can be greatly improved by making the ball easier to lift as a result of the spin amount.

The weight member 3 is, as shown in FIG.
Since it is along the inner wall surface 5i of the rib 5, it does not appear at all on the outer peripheral surface of the head 1, for example, the top portion g or the toe t.
The sole weight piece 9 only appears on a part of the surface of the sole s as shown in FIG. This makes it possible to prevent the finishing process of the head outer peripheral surface from being complicated while lowering the center of gravity, and to manufacture the head 1 at low cost and with high efficiency. A boundary line between the head body 2 and the weight member 3 is formed on the back face side, but the back face compared to the outer peripheral surface of the head including the top portion g, the toe t, and the like is formed of a substantially simple curved surface. Therefore, the finishing operation can be easily performed.

The sole weight piece 9 of this embodiment includes a toe-side sole weight piece 9A that fits into the toe-side cutout 6A and the heel-side cutout 6B, respectively.
The sole weight piece 9B on the heel side is included, so that the weight can be more effectively distributed and distributed to the toe and the heel of the head 1. In addition, each sole weight piece 9
A and 9B have insertion holes 3 into which the conical shaft 11 is inserted.
a (shown in FIG. 3A), respectively, and the head body 2
This facilitates the positioning and facilitates the fixation.

FIG. 4A shows an example of such a head 1.
As shown in (B), the shaft mounting portion 2b
At the design lie angle α.
In the reference state in which L is tilted to the horizontal plane H, not only the moment of inertia around the X axis, which is a horizontal axis along the face surface passing through the sweet spot SS of the head 1, but also
It is also possible to increase the moment of inertia about the Y axis, which is a vertical axis perpendicular to this, and it is possible to reduce the movement of the face around the Y axis when hitting the ball, for example, toward the heel or toe, and the flying can be reduced. This is preferable in that loss of distance and large deviation in directionality can be suppressed.

As shown in FIG. 4C, the length U of the sole weight piece 9 in the toe-heel direction along the sole S (when there are a plurality of sole weight pieces, each length U
The total length of 1, U2,... Is, for example, 10 mm or more, more preferably 30 mm or more, and further preferably 45 mm or more, from the viewpoint of lowering the center of gravity. Further, in this example, the length Q of the sole weight piece 9 in the sole width direction in the sole s is larger than the thickness T1 of the head body 2.

In this embodiment, the weight member 3 includes the backing material 10 so that the thickness of the face portion can be ensured, the rigidity of the face portion can be increased, and a firm shot feeling can be obtained. It is desirable that the thickness T2 of the backing material 11 be, for example, about 3 to 6 mm. The backing material 10 may cover the entire inside of the annular base 7 or may partially cover the sole S side as in this example.

In the present embodiment, as shown in FIG. 4A, in the reference state, the head 1 moves from the upper end 2e of the shaft mounting portion 2b to the center line CL of the shaft mounting portion 2b in the horizontal plane. The neck length L, which is the length up to the point K that intersects H, is set to a small length of 70 mm or less. This makes it possible to further lower the center of gravity of the head 1. However, if the neck length L is excessively small, the adhesion area between the shaft and the head 1 tends to decrease. Therefore, it is desirable to secure a length of preferably 30 mm or more, more preferably 35 to 70 mm.

When the neck length L is small as described above, the outer diameter D at the upper end 2e of the shaft mounting portion 2b is set to 13.2 mm or more, which is larger than the conventional one. Is desirable. This makes it possible to secure the weight of the shaft mounting portion 2b to some extent while keeping the length small.
For example, the center-of-gravity distance E of the head (the shortest distance from the sweet spot SS of the head to the center line of the shaft mounting portion 2b)
Can be effectively suppressed from becoming extremely large. Thus, it is possible to prevent the return of the head 1 from becoming worse. It is preferable that the outer diameter D is continuous at least 30 mm from the upper end 2e of the shaft mounting portion 2b to the sole side. If the outer diameter D is too large, the weight of the shaft mounting portion 2b becomes excessively large.
4.0-15.0 mm, more preferably 14.0-14.
Preferably, it is 6 mm.

The head 1 fits the head main body 2 and the weight member 3 by, for example, press-fitting, caulking, and fitting, welding, screwing, and brazing with an adhesive alone or two or more kinds. They can be joined in combination. In addition, it is particularly desirable to use a combination of a caulking and an adhesive which can provide a stable bonding strength and have a beautiful appearance.

FIG. 5 shows another embodiment of the present invention. In the head of the present embodiment, the face base 2a has a plate-like portion 4 forming the face surface F, and one face that protrudes toward the back face at the periphery thereof and extends annularly along the periphery and cuts off the sole s side. FIG. 3 illustrates a configuration having a rib 5 having a notch 6. The weight member 3 is
One sole weight piece 9 that fits into the notch 6
And the present example includes the backing material 10 partially disposed inside the annular base 7 and on the top side.

Although the embodiments of the present invention have been described in detail, the shapes, materials, and the like of the head body and the weight members are not limited to the illustrated embodiments, but may be variously changed and combined. For example, the rib 5 of the head body 2a
The head 1 may be provided with a bulging portion inside to make the back face side of the head 1 flat.

[0029]

FIGS. 1 and 5 show the effects of the present invention.
The golf club heads (Examples 1 and 2) shown in Table 1 were prototyped according to the specifications shown in Table 1 (both were No. I), and the performance was measured. For comparison, the same measurement was performed for the golf club heads (Comparative Examples 1 to 4) shown in FIGS. The outer diameter D of the upper end of the shaft mounting portion in Comparative Examples 1 to 4 is 1
3.0mm, and the neck length L is 71mm
mm, 48 mm, 71 mm and 60 mm.

The measured values are the height of the sweet spot from the horizontal plane, the moment of inertia around each of the X and Y axes (exponent values with the value of Example 2 being 100, the larger the numerical value is, the better), the center of gravity distance, The length of the neck and the outer diameter at the upper end were used. A golf club was prototyped by attaching a shaft to each head, and a swing robot and an average golfer 1
A test hit test with 0 people was also conducted.

In a test hit test using a swing robot,
The head speed at impact of the ball is 36 m / s,
And the side spin amount of the ball after launch is ± 200r
The golf ball was hit with a TOUR SPECIAL SOFT & METAL golf ball manufactured by Sumitomo Rubber Industries, Ltd., and the launch angle and the backspin amount of the ball were measured. Also, in the test hit test by 10 golfers,
20 balls from the grass on the fairway of the golf course
Each ball was hit, and the ease of climbing the ball and the degree of variation of the ball were evaluated on a five-point scale, and the average value of the evaluation of each golfer was shown. The evaluation shows that the larger the numerical value, the more easily the ball is raised, and the more difficult the ball is to vary.

Tables 1 and 2 show test results and the like. As is clear from the table, it can be confirmed that, in the head of the example or the golf club using the same, the ease of hitting is improved as compared with the comparative example, and the deterioration of productivity is also prevented.

[0033]

[Table 1]

[0034]

[Table 2]

[0035]

As described above, according to the first aspect of the present invention, the annular weight member made of the high specific gravity material is disposed along the rib formed on the peripheral edge of the plate-like portion forming the face surface. The head weight can be distributed more to the periphery of the head, and the moment of inertia can be increased. In addition, since the weight member includes a sole weight piece that is inserted into a cutout portion in which a rib is cut off on the sole side and forms a part of the sole portion surface, the center of gravity of the head is reduced, and the sweet spot height is reduced. It is possible to improve ease of hitting by reducing the ball and making it easier to raise the ball. further,
Since the weight member is arranged along the inner wall surface of the rib, it does not appear on the top portion or the toe portion forming the outer peripheral surface of the head,
Since it appears only on a part of the sole surface, the finishing step of the outer peripheral surface of the head can be prevented from being complicated while lowering the center of gravity, and the head can be produced inexpensively and efficiently.

According to the second aspect of the present invention, more weight can be distributed to each of the toe side and the heel side of the sole. This makes it possible to further increase the moment of inertia around the Y-axis, which is a vertical axis passing through the sweet spot of the head, in the reference state in which the head is solely set on a horizontal plane. Of the face around the Y axis can be reduced, and a loss in flight distance and a large deviation in directionality can be suppressed.

In the third aspect of the invention, the neck length L, which is the length from the upper end of the shaft mounting portion to the point where the center line of the shaft mounting portion intersects the horizontal plane, is set to 70.
mm or less to further lower the center of gravity of the head, while making the outer diameter D at the upper end of the shaft mounting portion 13.2 mm or more, to secure the weight of the shaft mounting portion to some extent and to maintain the center of gravity of the head. It is possible to effectively prevent the distance from being significantly increased, and to maintain the head easily returned.

[Brief description of the drawings]

FIG. 1 is a perspective view of a head according to an embodiment viewed from a back face side.

FIG. 2 is an exploded view thereof.

3A is a sectional view taken along line AA of FIG. 1, and FIG.
It is B sectional drawing.

FIG. 4A is a front view of a reference state of a head, and FIG. 4B is a side view thereof.

FIG. 5 is an exploded perspective view of a head according to another embodiment as viewed from the back face side.

FIG. 6A is a rear view of the head of Comparative Example 1, and FIG. 6B is a cross-sectional view along the line xx ′.

7A is a rear view of the head of Comparative Example 2, and FIG. 7B is a cross-sectional view taken along the line yy ′.

8A is a rear view of the head of Comparative Example 3, and FIG. 8B is a cross-sectional view taken along the line zz ′.

FIG. 9A is a rear view of the head of Comparative Example 4, and FIG. 9B is a cross-sectional view taken along the line vv ′.

FIG. 10 is a perspective view of a conventional head.

FIG. 11 is a sectional view taken along the line DD.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Iron type golf club head 2 Head main body 2a Face base 2b Shaft attachment part 3 Weight member 4 Plate part 5 Rib 6 Notch part 6A Notch part on toe side 6B Notch part on heel side 7 Annular base 9 Sole weight Piece 9A Toe side sole weight piece 9B Heel side sole weight piece s Sole t Toe h Heel g Top

Claims (4)

[Claims] 1. An iron-type golf club head having a head body provided with a shaft mounting portion for mounting a shaft on a heel side of a face base on which a face surface is formed, and a weight member, wherein the face base is A low specific gravity material having a specific gravity of 5.0 or less, a plate-like portion forming the face surface, a peripheral portion protruding to the back face side, extending annularly along the peripheral edge, and having a cutout on the sole side. The weight member is made of a high specific gravity material having a specific gravity of 7.0 or more, and has an annular base along an inner wall surface of the rib; An iron-type golf club head comprising: a sole weight piece formed on a sole side and fitted into the notch to form a part of the sole surface. . 2. The notch portion includes a toe side notch portion provided near the toe side and a heel side notch portion provided near the heel side, and the sole weight piece includes the toe portion. 2. The iron-type sole according to claim 1, further comprising: a toe-side sole weight piece fitted into the side notch, and a heel-side sole weight piece fitted into the heel side notch. Golf club head. 3. The shaft mounting portion has a cylindrical shape into which a shaft can be inserted, and has an outer diameter D of 1 at the upper end of a center line thereof.
3.2 mm or more, and in a reference state in which the center line of the shaft mounting portion is positioned in a vertical plane, and the center line is inclined at a design lie angle and soles on a horizontal surface, the shaft is mounted on the shaft from the upper end of the shaft mounting portion. 3. The iron-type golf club head according to claim 1, wherein a neck length L, which is a length up to a point at which a center line of the mounting portion intersects the horizontal plane, is 70 mm or less. 4. The iron according to claim 1, wherein the low specific gravity material is made of pure titanium or a titanium alloy, and the high specific gravity material is made of stainless steel, a nickel-copper alloy, a tungsten alloy or tungsten. Type golf club head.